Re: [PATCH v8 1/5] classes: add root filesystem containerizing class

["Bezdeka, Florian" <florian.bezdeka@siemens.com>]

On Mon, 2021-03-29 at 17:56 +0200, [ext] Silvano Cirujano Cuesta wrote:
> This class can be used to create container images which root filesystem
> is that generated by the do_rootfs task.
> 
> Containerized root filesystems have following possible use-cases:
>  - Using ISAR as a container image builder.
>  - Simplify distribution of runtime rootfs (binaries, libraries,
>    configurations, ...) for application development or testing.
>  - Distributing SDKs.
> 
> Signed-off-by: Silvano Cirujano Cuesta <silvano.cirujano-cuesta@siemens.com>
> ---
>  .../classes/image-container-extension.bbclass | 82 +++++++++++++++++++
>  meta/classes/image.bbclass                    |  1 +
>  2 files changed, 83 insertions(+)
>  create mode 100644 meta/classes/image-container-extension.bbclass
> 
> diff --git a/meta/classes/image-container-extension.bbclass b/meta/classes/image-container-extension.bbclass
> new file mode 100644
> index 0000000..f693627
> --- /dev/null
> +++ b/meta/classes/image-container-extension.bbclass
> @@ -0,0 +1,82 @@
> +# This software is a part of ISAR.
> +# Copyright (C) Siemens AG, 2021
> +#
> +# SPDX-License-Identifier: MIT
> +#
> +# This class extends the image.bbclass for containerizing the root filesystem.
> +
> +CONTAINER_FORMATS ?= "docker-archive"
> +IMAGE_INSTALL += "isar-exclude-docs isar-disable-apt-cache"
> +
> +containerize_rootfs() {
> +    local cmd="/bin/dash"
> +    local empty_tag="empty"
> +    local full_tag="latest"
> +    local oci_img_dir="${WORKDIR}/oci-image"
> +    local rootfs="$1"
> +    local rootfs_id="$2"
> +    local container_formats="$3"
> +
> +    # prepare OCI container image skeleton
> +    bbdebug 1 "prepare OCI container image skeleton"
> +    rm -rf "${oci_img_dir}"
> +    sudo umoci init --layout "${oci_img_dir}"

Sorry for replying to this quite old thread but the timestamp of the
commit actually delivered this patch as root cause:

Who makes sure umoci is available?

We updated to recent ISAR-next and got a build failure. umoci not
found.

Sounds like a missing IMAGER_INSTALL += "umoci" or similar.

Florian

> +    sudo umoci new --image "${oci_img_dir}:${empty_tag}"
> +    sudo umoci config --image "${oci_img_dir}:${empty_tag}" \
> +        --config.cmd="${cmd}"
> +    sudo umoci unpack --image "${oci_img_dir}:${empty_tag}" \
> +        "${oci_img_dir}_unpacked"
> +
> +    # add root filesystem as the flesh of the skeleton
> +    sudo cp -a "${rootfs}"/* "${oci_img_dir}_unpacked/rootfs/"
> +    # clean-up temporary files
> +    sudo find "${oci_img_dir}_unpacked/rootfs/tmp" -mindepth 1 -delete
> +
> +    # pack container image
> +    bbdebug 1 "pack container image"
> +    sudo umoci repack --image "${oci_img_dir}:${full_tag}" \
> +        "${oci_img_dir}_unpacked"
> +    sudo umoci remove --image "${oci_img_dir}:${empty_tag}"
> +    sudo rm -rf "${oci_img_dir}_unpacked"
> +
> +    # no root needed anymore
> +    sudo chown --recursive $(id -u):$(id -g) "${oci_img_dir}"
> +
> +    # convert the OCI container image to the desired format
> +    image_name="isar-${rootfs_id}"
> +    for image_type in ${CONTAINER_FORMATS} ; do
> +        image_archive="${DEPLOY_DIR_IMAGE}/${rootfs_id}-${image_type}.tar"
> +        bbdebug 1 "Creating container image type: ${image_type}"
> +        case "${image_type}" in
> +            "docker-archive" | "oci-archive")
> +                if [ "${image_type}" = "oci-archive" ] ; then
> +                    target="${image_type}:${image_archive}:latest"
> +                else
> +                    target="${image_type}:${image_archive}:${image_name}:latest"
> +                fi
> +                rm -f "${image_archive}" "${image_archive}.xz"
> +                bbdebug 2 "Converting OCI image to ${image_type}"
> +                skopeo --insecure-policy copy \
> +                    "oci:${oci_img_dir}:${full_tag}" "${target}"
> +                bbdebug 2 "Compressing image"
> +                xz -T0 "${image_archive}"
> +                ;;
> +            "oci")
> +                tar --create --xz --directory "${oci_img_dir}" \
> +                    --file "${image_archive}.xz" .
> +                ;;
> +            "docker-daemon" | "containers-storage")
> +                if [ -f /.dockerenv ] || [ -f /run/.containerenv ] ; then
> +                    die "Adding the container image to a container runtime (${image_type}) not supported if running from a container (e.g. 'kas-container')"
> +                fi
> +                skopeo --insecure-policy copy \
> +                    "oci:${oci_img_dir}:${full_tag}" \
> +                    "${image_type}:${image_name}:latest"
> +                ;;
> +            *)
> +                die "Unsupported format for containerize_rootfs: ${image_type}"
> +                ;;
> +        esac
> +    done
> +}
> +
> diff --git a/meta/classes/image.bbclass b/meta/classes/image.bbclass
> index eddc444..ec93cab 100644
> --- a/meta/classes/image.bbclass
> +++ b/meta/classes/image.bbclass
> @@ -76,6 +76,7 @@ inherit image-tools-extension
>  inherit image-postproc-extension
>  inherit image-locales-extension
>  inherit image-account-extension
> +inherit image-container-extension
>  
>  # Extra space for rootfs in MB
>  ROOTFS_EXTRA ?= "64"
> -- 
> 2.30.2
>